HUTABARAT, Nengsi Mita; SIMORANGKIR, Murniaty. Pengembangan E-modul Pembelajaran Kimia Berbasis Problem Based Learning Pada Materi Sistem Periodik Unsur. Reflection Journal, [S. l.], v. 5, n. 2, p. 709–717, 2025. DOI: 10.36312/rj.v5i2.3300. Disponível em: https://journal-center.litpam.com/index.php/RJ/article/view/3300. Acesso em: 19 jan. 2026.